1. Field of the Invention
The present invention pertains to side looking radars for use on vehicles, such as airplanes and the like, to observe moving targets and determine the speed and direction of movement thereof. It has long been a desire of various organizations, such as military, to be able to determine the direction and speed of moving targets from an airplane or other vehicle with a side looking radar.
2. Prior Art
Previous attempts at determining the speed and direction of moving targets by using side looking radars have incorporated such unwieldly apparatus and methods as two aircraft, one behind the other, each having a side looking radar. Another method is the use of a single aircraft with a side looking radar flying a predetermined course, such as a racetrack type course. Because of time lag, differences in equipment and many other variables these methods have not been able to provide a useful and accurate determination of target speed and direction. Other types of radar and methods, such as measuring a Doppler effect, have been attempted but inaccuracies and interferences render these systems relatively useless for accurate determination of speed and direction of moving targets.